1. Department of Pediatrics, Division of Pediatric Respiratory Medicine, Inselspital, Bern University HospitalUniversity of BernBern Switzerland
2. Department of Pediatrics and Adolescent MedicineTeaching Hospital University of ViennaWilhelminenspital Vienna Austria
3. Department of Pediatric Cardiology and Intensive Care Medicine with Neonatology and Pediatric PneumologyUniversity Hospital GoettingenGoettingen Germany
4. Department of PediatricsUniversity Hospital Halle (Saale)Halle Germany